19 of the All-Time Best Core Exercises that Will Get You in Incredible Shape

Plank

1. Assume a plank position, resting on your elbows, with the balls of your feet about shoulder width apart. Your elbows should be directly underneath your shoulders, your back should be flat, and your neck should form a straight line with your back. Tighten your rear end and abdominals and the front of the thighs.
2. Hold this position for the suggested amount of time. Do not allow your lower back to sag.

What it does: Strengthens the entire core.

Form tip: To intensify this exercise, narrow your base of support by moving your feet closer together. (Try these plank exercises to perform your abs.)

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